3-18
Signal Descriptions
•
MAD[6] – Reserved.
•
MAD[5] – Reserved.
•
MAD[4] – Reserved.
•
MAD[3:1] – These pins set the size of the external expansion ROM
device attached.
provides the encoding for these pins. A
“0” indicates a pull-down resistor is attached while a “1” indicates a
pull-up resistor attached.
•
MAD[0], slow ROM – When pulled up, this pin enables use of slower
memory devices by including two extra data access cycles.
Note:
All MAD pins have internal pull-down resistors.
Table 3.15
MAD[3:1] Pin Decoding
MAD[3:1]
Available Memory Space
000
16 Kbytes
001
32 Kbytes
010
64 Kbytes
011
128 Kbytes
100
256 Kbytes
101
512 Kbytes
110
1024 Kbytes
111
no external memory present
Содержание LSI53C1000
Страница 6: ...vi Preface...
Страница 16: ...xvi Contents...
Страница 28: ...1 12 Introduction...
Страница 234: ...4 124 Registers...
Страница 314: ...6 40 Specifications This page intentionally left blank...
Страница 318: ...6 44 Specifications This page intentionally left blank...
Страница 344: ...6 70 Specifications This page intentionally left blank...
Страница 350: ...6 76 Specifications Figure 6 42 LSI53C1000 329 Ball Grid Array Bottom view...
Страница 352: ...6 78 Specifications...
Страница 360: ...A 8 Register Summary...
Страница 376: ...IX 12 Index...